Apparatus for making, removing, and processing soap and the like



B. H. THURMAN Filed Sept. 26, 1935 APPARATUS FOR MAKING, REMOVING, AND PROCESSING SOAP AND THE LIKE 75 W xf-g 52 77 z 773 '75 72 I f L 6 /e '3' @Mia 653 B A TTOE/VEK Jan. "2, 1940. B. H. THURMAN APPARATUS FOR MAKING, REMOVING, AND PROCESSING SOAP AND THE LIKE 2 Sheets-Shea?I 2 Filedv Sept. 26, 1935 Patented Jan. 2, 1940 `UNITED STATES PATENT OFFICE APPARATUS FOB MAKING, REMOVING, AND PROCESSING SOAP AND THE LIKE Benjamin n. Thurman, mamme, N. Y., signi or to Refining, Inc., Reno, Nev., a corporation of Nevada Application September 26, 1935, Serial No. 42,348

Claims.

method of making soap involves introduction into f' a heated tube of saponifying and saponifiable materials. These materials are heated in the tube during mild turbulent iiow therethrough, the heating being carried to a degree determined by the desired water content of the soap to be produced and by other factors involved in soap production. Saponication takes place under these conditions of relatively high temperature, and it is usually desirable to build up considerable pressure in the tube to facilitate the desired reactions.

The friction of the materials forced through the tube tends to build up such a. pressure, but in some instances it is desirable to supplement this actionfby .use of a restricted orifice through which the reaction products move upon being discharged from the tube. If these products are discharged into a low-pressure zone, the soap particles will drop to the lower end thereof. The conditions of temperature and pressurein the tube may be such that all of the water is vaporized before reaching the restricted orifice, in which eventthe steam -expands after discharge from this orifice and can be readily separated from the soap. On the other hand, conditions of temperature and pressure in the tube may be such that only a portion `of the water is vaporized in the tube, all or a portion of the remaining water flashing into steam upon entry into 'the low-pressure zone. If temperature and pressure conditions are properly regulated, -soap may be formed even without vaporization of water in the tube, though the temperatures may be such that a portion of the water will flash intor steam upon introduction into a low-pressure zone. Certain features of the invention, such as the soap-removal system, are of utility regardless of which of these methods is used for producing the soap.

However, other features of the invention are 50 directed particularly to methods of soap production involving vaporization of allor a part of the water in the tube..

In` the event that giycerine is to be recovered, it is necessary to heat the materials in the tube to such an extent that all of the water is convetted into steam therein. All or a portion of the glycerine formed by the soap-making reaction mayalso be vaporized in the tube. As to any unvaporized glycerine, all or a portion there- .low-pressure zone. The water and glycerine vapors can be withdrawn from the low-pressure zone and ,fractionally condensed. In this instance the resulting soap is in the form of small anhydrous particles if insumcient heat is applied to form molten soap.

On the other hand, high pressures can be maintained in the heated tube without provision of a restricted orifice by utilization of a relatively long tube of small cross-sectional area. 'I'he fric- L'tional forces developed by flow of the materials therethrough may be made suilicient to develop the desired pressures in the tube, and conditions of pressure and temperature may be such that considerable or all of the water and even'the glycerine is vaporized in some portion of the coil, When utilizing frictional forces in this pressurebuilding capacity. itis sometimes desirable to discharge the reaction products from the tube whether or not it is anhydrous, and the conveyor system of the present invention will he described with reference to the removal of this soap and any vapors formed.

It is an object of the present invention to provide a no vel conveyor means for withdrawing material from a low-pressure zone without ,destroying the partial vacuum therein, while continuously withdrawing and recovering glycerine from the low-pressure zone. It is another object of the present invention to provide in such a. soap-making system as discussed above a novel method and apparatus for removing soap from the low-pressure zone.

It is a further object of the invention to pro- 'vide a method of removing soap particles, and of processing same, as by cooling, adding water or other material thereto during ow, etc., and it is also an object of the present invention to provide a novel apparatus adapted to thus remove and process the soap.

Another object of the invention is to continuously compress soap particles withdrawn from,

a chamber, the compressing step being either carried to such a degree as to form a solid homogeneous mass of plastic soap, or to form 'a solid mass of soap particles pressed together temporarily, and included among the objects of the present invention is the provision of a novel apparatus for performing this method.

It is another object of the invention to provide a novel method and apparatus for subjecting the soap to a milling or plodding action.

Other novel features of the present invention relate to the soap-forming process and apparatus, it being an object of the present invention to suitably control the temperatures in the lowpressure zone, and, in one embodiment, to supply steam to this low-pressure zone to facilitate the removal of glycerine from the soap.

It is another object of the present invention to provide a novel method and apparatus facilitating complete separation of the'vapors from the soap in the low-pressure zone.

Still a further object of the invention is to provide a novel method and apparatus for conserving heat in such a soap-making process.

Further objects and advantages of the invention will be evident to those skilled inthe art from the following description of a typical installation.

It will be clear, however, that the embodiment to be hereinafter described in detail is selected only for illustrative purposes, and that various changes and modifications may be made without departing from the spirit of the invention.

Referring to the drawings,\which are purely diagrammatic, and which make no attempt to show the various elements in proportional size:

Fig. l illustrates a continuous soap-making system.

Figs. 2 and 3 are sectional views taken on corresponding lines of Fig. i.

Fig. 4 illustrates a reciprocating soap-removing system.

In Fig. l the numeral l indicates a mixing apparatus, 2 is a heater, 3 is a vacuum kettle or container in which the soap is deposited, l is a first conveyor, 5 is a pressure seal, 6 is a second conveyor, l is an extrudlng means, 8 is a glycerine condenser, and 9 is a water condenser.

The function of the mixing apparatus l is to deliver to the heater 2 properly proportioned saponifying and saponiflable materials, preferably preliminarily mixed by action of the mixing apparatus to such a degree that the saponifying material is uniformly dispersed throughout the saponifiable material. The saponiflable material may be any material capable of being saponined to form soap, such, for instance, as fat. The saponifying material may be any material which will react with the saponiflable material to form soap, usually an aqueous solution of a saponifying alkali such as caustic soda.

The mixing apparatus illustrated includes a pair of proportioning pumps respectively designated as an alkali pump Il and a fat pump l2, the latter being driven by a suitable drive means I3. A speed-changing device I4 interconnects the pumps H and l2. The fat, or other saponiflable material, is taken from a fat tank i8 and pumped into a mixer I1. The c austic soda, or other saponifying material, is pumped from a tank i8 and delivered to the mixer I1. The streams of saponifying and saponiable materials are preliminarily mixed in the mixer I1 and flow through a pipe i9 to a coil 2| of the heater 2.

'I'he function of the heater 2 is to effect saponitcatlon of the materials under considerable heat and pressure, such temperatures preferably being utilized as will vaporize all or a portion of the water in the saponifying material. As illustrated, this heater includes an outer shell 23 surrounding a tube which is bent to form a coil 2l, this coil being heated by any suitable means such as a burner 24 supplying products of combustion which pass upward through the outer shell 23 exterior of the tubing forming the coil 2l. The pumps Il and l2 force the materials into the coil at a relatively high pressure, acting against the pressures developed in this coil. The inlet pressures on the coil may be several hundred pounds per square inch if desired, though a pressure drop takes place in the coil so that the pressure near the discharge end of the coil may be in some instances from 150 to 200 pounds per 'square inch lower than the inlet pressure. The reaction products are delivered from the lower end of the coil 2| through a pipe 26, which may be provided with a thermometer 21 and a pressure gauge 28, these products being in some instances discharged into the low-pressure zone through a nozzle 29 providing a restricted orifice.M In practice we have found it desirable to employ heat insufncent to render the soap stock in the lowpressure zone molten, such, for example, as temperatures ranging from 500 F. down to, say. 45o F.

The primary function of the vacuum kettle or container 3 is to collect the soap preliminary to removal, and to effect separation of the vap'ors. structurally, this vacuum kettle or container provides a low-pressure zone 3l into which the relower end to form a hood, the diameter thereof being somewhat less than the container 3 to provide an annular space 33 through which the vapors move upward in a manner to be hereinafter described. With this construction the reaction products are introduced into the space inside the inner shell 32, Fig. 1 illustrating the nozzle 29 discharging therein. However, as previously mentioned, it is not invariably necessary to utilize such a constricted orifice. Regardless of Whether or not the nozzle 29 is utilized, it is possible by suitable manipulation to form minute solid soap particleswhich move downward in the low-pressure zone, collecting in the bottom of the inner shell 32 in the absence of a means for continuously removing same.

To insure-delivery of this soap to the first conveyor 4, a suitable agitator means is provided including one or more agitator arms 35 suitably secured to the shaft 36 and moving in the zone directly beneath the lower end of the inner shell 32. 'A thrust bearing 31 journals the shaft 36 and is mounted on arms 38 extending inward from the inner shell 32. this inner shell being held in xed position by spacers 38a. Suitable packing means is provided for sealing the junction of the shaft 36 and the container 3, though it is not necessary to tightly seal the junction of the shaft and the inner shell 32, a wiping joint being satisfactory. A motor 39, or other drive means, is utilized for slowly rotating the shaft 36 so that the agitator arms 35 continuously stir the soap particles in the lower end of the lowpressure zone 3l. If desired, these arms may be inclined so as to pressurally force the soap downward toward the rst conveyor 4.

housings 42 and 43 providing a low-pressure passage in which the soap particles are advanced. The housing 42 may extend across the container 3, being open at its upper portion to receive the l soap particles.

The soap being conveyed by the first conveyor 4 is in a highly heated condition, for example, 450 F. An important characteristic of our invention 'fis to providemeans for cooling the said soap down to a point wheresubsequent hydration can be effected. For that purpose, a pipe 44, suitably valved, may be communicated directly with the low-pressure passage for introducing a desirable cooling medium which may be discharged at a plurality of points around the housing 43, and structure 45 may surround this housing to provide an annular chamber communicating with the pipe` 44, suitable openings being formed in this housing to deliver the cooling medium to the soap. The coolingmedium is desirably water, although, of course, other agentsA may be employed.

If desired, other materials, such as builders,

etc., may be added to the soap being conveyed' Sure passage.

I preferably also cool the soap passing through the rst conveyor 4 by providing a jacket 41 around the housing 43. Any suitable medium can be circulated through this jacket to cool the soap, but I find it sometimes desirable to pre-heat the saponiable material by forcing the same through thisjacket and then through a pipe 41a to the fat tank I6. This effects considerable saving of heat and also preliminarily heats the fat or other saponiflable material in degree proportional to the temperature of the resulting soap. 1

Irrespective of what means areemployed for effecting the cooling step, I have found it desirable in practice to cool the soap down to, say,

200 F. to 250 F. in order that water subse-v quently introduced in a manner hereinafter described, to the soap being conveyed by the second conveyor, may effectively hydrate the same to the desired extent, depending upon the moisture content required in the final product.-

Suitable means is provided for rotating the screw 40. As shown, this means includes a countershaft 48 driven by a suitable drive means, not shown, and suitably geared to the shaft 4I of the screw 40. The direction of rotation of the screw 40 is such that the soap particles are advanced to the right, as shown fin the drawings, being discharged into a chamber 50. This chamber is at sub-atmospheric pressure, though the pressure therein may be somewhat higher than the pressure in the low-pressure zone 3l.

The function of the pressure seal 5 is to convey the soap particles from the chamber 50 to a chamber 52 Awhich may be of the same or somewhat higher pressure. The sealing action of this device is particularly important if the pressure in the chamber 52 is higher than the pressure in the chamber 50, in whichinstance the device functions to conduct the soap particles without too greatly impairing the vacuum in the chamber 50. 'Ihis pressure seal may be in theform of a star valve diagrammatically shown as including a casing 55 communicating with the chamber 50. A rotor 5I is adapted to turn in the casing 55 and provides outward-extending blades arranged with such clearances as to maintain the partial vacuum in the chamber 50. This rotor vis preferably driven by a suitable drive means, the embodiment shown utilizing a gear connection between the rotor and the countershaft 48. The soap discharged from this starV valve drops through the chamber 52 and into the second conveyor 5.

The function of the second conveyor, if used, is to further transport the soap, and, if desired, to compress and process vby milling or plodding these particles. Depending upon the composition of the soap particles originally produced, the water or other material added, the degree of cooling, thedegree of compression developed, and the degree of milling or plodding, it is pos- -sible to'obtain either one or more continuous streams of plastic ba-r soap, or a compact mass of individual soap particles temporarily adhering but which can be readily broken up after being discharged from the second conveyor 6. Another function which may be performed by the second conveyor 6 is to provide a moving plug of soap which assists in preventing entry of air into the low-pressure chambers of the system, thus serving as a seal to prevent loss of Vacuum therein.A A further function o f this conveyor may be to introduce liquid or powdered builder or other added material into the soap.

structurally, the second conveyor 6 is shown .as including a rotatable member 51 and a stathrough. If desired, 'the cooling of the second conveyor may be effected by spraying water di rectly upon the housing 6i.

-If it is desired to compress the soap, the annular space 63 between the coaxially arranged stationary and movable members may be tapered yas shown so as to provide a larger cross-sectional area at that end into which soap is introduced, this cross-sectional area progressively decreasing toward the end communicating with the extruding means 1. One convenient way of forming i such an annular tapered space is to utilize a taperedfshaft 59 with the vane means 60 extending outward therefrom and substantially across lthe tapered annular space 63. It is further desirable to so form the vane means 60 that the pitch thereof'I is greater near the inlet end than near the discharge end. Such a structure permits considerable pressing of the soap during ,l

continuous advancement thereof in the tapered annular space 63.

It is often desirable to use auxiliary means for breaking up the continuous soap body being advanced by the second conveyor 6. With certain soaps there is a tendency for the soap to wedge between the vane means in the tapered annular space 63, thus tending to prevent the proper feed and extrusion of the soap material. So also, it is often desirable to subject the advancing soap materials to a milling or plodding action. Prevention of wedging and accomplishment of this desirable milling or plodding action are effected by utilization of one or more means for breaking up the continuous soap plug at one ormore points disposed along the second conveyor 6. For instance, the vane means may be formed in sections and a perforated plate means 64 interposed therebetween, the soap being forced through the perorations by the preceding section of the vane means` and being again picked up and advanced by the succeeding section of the vane means. Fig. 2 illustrates such a perforated plate means 64 as including two semi-circular plates suitably secured in the housing 6| as by screws 65.

Figs. l and 3 illustrate another form of such a means for breaking up the continuous soap stream and which may be used alternately or in conjunction with the perforated plate means disclosed in Fig. 2. In this form a series of pins or knife bars 66 may be suitably secured in the housing 6i extending inward substantially across the tapered. annular space 63. These 'pins or knife bars 66 are positioned between adjacent sections of the vane means 60. Being stationary, they break up the stream or plug of soap being advanced along the second conveyor 6. Such perforated plates or knife bars may be disposed at one or more points along th'e second conveyor 6, and may also be used in conjunction with the first conveyor 4 if desired. It will furthermore be apparent that it is not necessary to utilize both forms of these devices, as shown respectively in Figs. 2 and 3, in conjunction with each other, for either form may be separately used to secure the desired milling and plodding effect, as well as to break up the stream or plug of soap which might otherwise tend to wedge in the tapered annular space 63. In other instances, however, such devices can be dispensed with.

Following the cooling step effected in the first conveyor, as above described, the temperature of the soap particles has been materially reduced by the time the soap has reached the second conveyor 6. The soap during its passage through the second conveyor may, therefore, be hydrated to the desired extent by introducing water through the pipe 61 suitably valved. This pipe may communicate directly with the soap moving in the tapered annular space 63 or may communicate with a structure 68 surrounding the housing 6l and providing a chamber 69, supplying the added material to the soap through a plurality of openings provided by the housing and disposed peripherally therearound. A very uniform mixture of soap and this added material is obtained in the second conveyor 6, regardless of whether the materialis introduced at a single point or a plurality of points peripherally spaced.

Rotation of the rotatable member 51 may be effected by any suitable drive means, the embodiment illustrated including geared means interconnecting the tapered shaft 59 and the countershaft I8. Such an interconnected system is particularly advantageous in view ofthe fact that the first and second conveyors 4 and 6, as

well as the rotor 56 of the star valve, are moved proportionately.

The function of the extruding means 1 is to exert back pressure on the soap mass, and to extrude the soap either as a solid homogeneous mass in bar or filament form if the soap is of such character as to assume this form, or as a powder or compacted mass of particles temporarily adhering but which may subdivide upon extrusion, or be readily broken up after extrusion. If the soap is extruded in bar or filament form, such bars or filaments may be cut off as desired.

structurally, this extruding means 'l may include a quick-opening valve means such as a Yarway valve of the swing-gate type, and, if desired, used in conjunction with a screen or perforated member forming the discharged soap into vermicelli-like filaments. The form illustrated in Fig. l may perform both the function of a valve and a subdividing means for the soap. As shown therein, the extruding device includes a cap 72 suitably secured to the housing 6| and definingL a chamber 1l. This cap provides one or moreorifices 13 which communicate between the chamber 1I and a quick-opening valve plate 75. l

This plate may be journalled on a pin 'l1 retained in the cap 12, and a handle 18 may be provided for turning this valve plate to bring openings 19 thereof into or out of communication with the orifices 13. The size of the openings 'I9 will determine the size of the soap-stream extruded therethrough. However, in some instances it is possible to dispense with the valve plate '15, or to substitute for the extruding means 1 any suitable valve structure either with or without a perforated means such as provided by the openings 19 to discharge a plurality of soap streams rather than a single soap stream. So also, a valve of the spring-type such as disclosed in Fig. 4 may be substituted for the extruding means 'l without departing from the spirit of this invention.

If desired, the cap T2 may be utilized for journalling the shaft 59 of the rotatable member 51, though this is not necessary. The housing 6l serves to journal this rotatable member throughout its length. So also, the soap being compressed acts as a bearing means for the rotatable member.

In the soap-making process herein disclosed, it is often desirable to be able to regulate the temperature inside the container 3. Temperature conditions therein may be controlled by utilizing a jacket 8| surrounding all or a portion of this container, a suitable medium being circulated therethrough for regulating temperature conditions. As shown, this jacket surrounds only the lower portion of the container 3, but it will be clear that it may be extended upward to surround substantially the entire surface thereof if desired. l

In addition, it is often desirable to introduce steam into the low-pressure zone inside the container 3. 'I'his steam serves to further control temperature conditions therein. Thus, by using high-temperature or superheated steam it is possible to increase the temperature of the reaction products to cause liberation of additional vapors from the soap. For instance, if the glycerine has not been completely removed from the soap, additional heat can be supplied to the soap by the introduction of steam or by utilization .of the jacket 8l to maintain the soap under sufficient temperature to liberate additional quantities of the glycerine. So also, the application of additional heat to the low-pressure zone prevents condensation of glycerine vaprs which may have previously separated. thus preventing the condensed glycerine from returning to the soap. In addition, the steam' introduced into the lowpressure zone helps to carry away the glycerine already volatilized. It also makes possible-the operation of the soap-forming system at lower temperatures than would otherwise be necessary. By way of example, lower temperatures can be utilized in the reaction zone defined by the coil of the heater 2 to secure very desirableresults, additional heat being supplied to the low-pressure zone through the jacket 9| or through steam introduction. In addition, the steam plays a very important part in assisting in the distillation of the glycerine by the principle of partial vapor pressures in the low-pressure zone. Thus, if steam is introduced thereinto, it is not necessary to carry as high a vacuum in the low-pressure zone as would otherwise be necessary to secure l the results desired.

Fig. 1 discloses several ways of introducing steam into the low-pressure zone. One very effective way is to introduce steam through a pipe 02, the flow being controlled by, a valve 93. In this instance the steam is discharged through a nozzle 04 so directed as to impinge the steam against the reaction products discharged from the nozzle 29. In some instances it is preferable to introduce the steam at a plurality of points in the low-pressure zone. If such a mode of injection is desired, a valve 85 maybe opened, allow ing the steam to move through a pipe 39 into a chamber 91 defined by the shaft 36, the steam being discharged through a plurality of orices .99 into or adjacent the reaction products discharged into the low-pressure'zone. In other instances it is advantageous to introduce the steam through a passage 99 surrounding a portion of the pipe 29, this 'passage being defined between the pipe 26 and a pipe 90. A valve 9| controls the flow of steam, and it will be ap'- Vparent that an annular jet of thesteam is discharged around the nozzle 29. This system is particularly advantageous in uniformly distributing the steam in the reaction products discharged from the nozzle 29. It also is advantageous in that the steam heats the reaction products flowing through the pipe 20 before discharge from the nozzle. 29, the steam thus heating the reaction products both before and after 'discharge from this nozzle. Any one of these steam-introduction systems may-be used individually, or a plurality thereof may be simultaneously utilized.

The vapors which separate from the soap inside the inner shell 32 move downward with the soap, flowing beneath the lower edge of this inner shell 32 and rising in the annular space 33. I prefer to provide a helical baille 93 in the annular space 33 so that the vapors'rlsing in this space are guided through a helical path. In addition, a conical baffle 94 may be utilized above the inner shell 32 to further deflect the rising vapors through paths as indicated by the arrows inl Fig. 1.

The vapors leave the upper end of the conprovided with intermediate heads 99 between which tubes extend to conduct' the vapors upward therethrough. 'I'he space between the heads 99 inside the shell 99 and around the tubes |00 is filled with a circulating cooling medium in the usual manner. Any condensate produced in -the glycerine condenser 8 passes downward through a pipe |0| to a glycerine tank |02. This pipe is sufliciently long to permit maintenance of a high degree of vacuum in the glycerine condenser 0, the lower end of this pipe being submergedin the glycerine inthe tank |02.

Any gases or vapors which are not condensed in the glycerine condenser 0 move through a pipe |03 to the water condenser 9, which may be of the jet type supplied with cooling water through a pipe |04. 'I'he water condensed therein, and the cooling water supplied thereto, move downward in a pipe to a water tank |06. II'he pipe |00 is suillciently long to permit 'maintenance of a high degree of vacuum in the water condenser 9, and the lower end of this pipe is submerged in the water in thetank |00. A suitable vacuum pump ||0 is provided for maintaining the container 3 and the condensers I and 9 under subatmospheric pressures. Usually it is desirable to maintain a relatively high vacuum in these portions of the apparatus, especially if glycerine is -to be recovered.

The mixing apparatus is so adjusted as to confact, if the system is to be operated in a'. manner to recover-glycerine, it is necessary, in the absence of a large amount of heat supplied t'o the low-pressure zone, to vaporize all of the water in the coil and usually at least a part of the glycerlne. If the restricted orifice formed by the 'nozzle 29 is used, a portion or all of the unvaporized glycerine may be allowed to ash into vapor upon discharge into the low-pressure zone.

So also. heat applied to the low-pressure zone either externally, from the jacket -|i|, or inte'rnally, by introduction of steam into this zone, will cause formation or liberation of additional vapors.

It will be clear, however, thatit is not necessary to remove any or all of 'the glycerine from the soap in the event it is desired to produce a soa-p containing glycerine. If the glycerine is to be allowed' to remain therein, the system can be operated at lower temperatures. Thus it is possible to produce substantially anhydrous soap by vaporizing only the water, the system being so regulated that the water goes into the vapor phase either in the coil or in the low-pressure zone or in both. If the soap is not to be substan- `tially anhydrous, it is possible to vaporize only a this example is set forth only as illustrative of 'one possible set of conditions and not as limiting the invention thereto. The system may be operated with the pressure gauge 28 indicating a pressure of approximately 100 pounds per square inch (gauge), the temperature indicated by the thermometer being around 440 F.v The pressure at the inlet end of the coil will be considerably higher due to the friction drop in the coil. This drop may be 100 pounds per square inch, or more in some installations. It will be understood that considerably less heat need be supplied through the walls of the tube forming the coil if the low-pressure zone is externally or internally heated, the heat supplied at this point permitting formation of water or glycerine vapors, or both, as desired. So also, addition of steam to the low-pressure zone acts, by the law of partial pressures, to permit somewhat higher pressures in this zone during glycerinerecovery operation.

If a restricted orifice such as provided by the nozzle 2S is utilized, the reaction products are discharged into the low-pressure zone with considerable velocity. However, this velocity drops very rapidly, and as the velocity is reduced, the vapors readily separate from the soap particles. I nd it very advantageous to utilize the inner shell 32 tol insure that the vapors will travel in the same direction as the soap until they reach the lower portion of this inner shell. This facilitates the separation of the ne soap dust, preventing the vapors from carrying this finer material upward therewith, though it will be clear that this inner shell 32 may be dispensed with in some instances. It will further be clear that when such an inner shell 32 is utilized, the pressure inside thereof may be slightly higher than the pressure in the annular space 33. This is unobjectionable and in some instances is advan- After passing beneath the lower edge of this inner shell 32, the upward movement of the vapors is retarded by the helical vane means 93 which moves these vapors in a helical path, thus tending to further separate any extremely small soap particles. The catch-all 96 removes any remaining soap particles and the vapors are fractionally condensed in the condensers 8 and 9 as previously described. It will be clear that these vapors may include only water vapor, or may include water vapor and glycerine vapor, depending upon the mode of operation of the system. If only water vapor is present, it is, of course, unnecessary to utilize two condensers.

The soap particles are continuously stirred by the agitator so that they drop into the low-pressure passage of the first conveyor 4. It is often desirable to somewhat cool the soap particles therein, this being readily accomplished by flowing the saponiable material or other cooling material through the jacket 41 and even by the addition of materials through the pipe 44. This cooling is often desirable to prevent darkening or discolorng of the soap particles, which tends to take place if anhydrous particles are maintained at high temperature for a prolonged time and exposed to air. Further, it is desirable to cool the soap particles before introducing additional moisture or other material thereinto through the pipe 61 in order that adequate hydration can be secured. It is not desirable, however, to cool the soap to such an extent that no vaporization whatsoever of the water takes place when it is introduced into the second conveyor through the pipe Sl. Thus, it is desirable to maintain the soap sufliciently hot so that the water which it may be desired to introduce through the pipe 61 will in part vaporize to cause an even distribution of the water, thus insuring uniform hydration of the soap. The relationship of the cooling step to the hydration step can be varied in order that a predetermined moisture content of the nal product is obtainable. This cooling step also involves considerable saving in heat, the heat transfer between the saponiable material and the soap being very effective to preliminariiy heat this material in proportion to the temperature of the soap produced.

Any excess steam formed by introducing water or other liquid through the pipe' 44 will rise through the pipe 46 to the low-pressure zone 3l. It will be clear, however, that the invention is not limited to the cooling of the soap at this point.

When the soap particles reach the discharge end of the first conveyor 4, thry drop into the chamber 50 and enter the spaces between the blades of the rotor 56 of the star valve. A suiiicient number of blades is provided so that an effective seal is maintained at all times regardless of the position of the rotor. It will be clear, however, that the chamber 50 will be under subatmospheric pressure, though the pressure therein may be somewhat higher than the pressure in the low-pressure zone 3| due both to the pumping action of the screw and the material introduced into the soap through the pipe 44.

The particles of soap drop from the star valve into the chamber 52 and thence into the second conveyor 6. The system may be so operated that a material pressure differential exists between the chambers 5U and 52, or it may be operated in such a way that these chambers are at substantially the same sub-atmospheric pressure.

The second conveyor 6 may serve to transport the soap without compression, though it is usually desirable to utilize a system which compresses or compacts the soap during passage therethrough. Depending upon the degree of compression, the degree of cooling, and the materials added, the soap may be extruded from the extruding means 'I either as a compact mass or stream of plastic soap or as a compressed, compacted mass of temporarily adhering soap particles which either separate upon extrusion or which can be readily broken up. The term compressed mass of soap is herein utilized to cover all such forms. In any instance, the resulting soap product can be used as produced, or may be run through a series of plodders or through milling rolls, being pressedA and stamped into ilnished cakes of soap.

If used, themeans for breaking up the soap stream, such as illustrated in Figs. 2 and 3, serve the very desirable function of subjecting the soap to a milling or plodding action during movement by the conveyor means. I'hey also tend to prevent clogging of the conveyor system through wedging of the soap mass in the tapered annular space 63. It will be clear that while I have disclosed such means only in conjunction with the second conveyor 6, similar means may be applied to the rst conveyor 4 if desired.

One of the important functions which may be performed by the second conveyor 6 is to provide a seal or plug of soap to prevent air leaking back through the second conveyor 6 to the star valve. The tapered annular space 63, as well as the constricted opening or openings of the extrudlng device, assists in building up a back pressure which so compacts the soap as to form such an effective seal or plug. It will be understood, however,that this sealing action is supplementary to the sealing action of the star valve, and that in some instances it is possible to utilize the star valve with or without the second conveyor 6 for preventing entry of air into the chamber 50 ,and the low-pressure zone 3| in such quantity as to impair the partial vacuum ,which it is desired to maintain therein.

If desired, the successive cooling and hydration steps, respectively, may be performed during the passage of the soap particles in the first conveyor. Powdered or liquid builders may be introduced in any desired manner. As stated, the soap may be additionally cooled through the conveyor 6 by circulating a cooling medium through the jacket 62.

It will further be apparent that pressure on the soap progressively rises either in infinitesimal steps along the conveying system, or in nite steps, such, for instance, as when a material pressure differential exists on opposite sides of the star valve.

The degree of vacuum maintained in the lowpressure zone 3|, and the amount of heat sup-- plied to the heater 2, will depend upon the product to be produced, and will depend upon whether or not the glycerine is to be recovered by condensation or is to be allowed to remain in the soap. Regardless of the moisture or glycerine content of the soap, however, the conveying system permits continuous removal of the soap particles from the low-pressure zone 3| without breaking the vacuum. This is true even though sumcient heat is supplied to the container 3 through the jacket 8| or through steam introduction to maintain the soap in the low-pressure zone 3| in liquid or semi-liquid condition. While it is not always essential to circulate a heating medium through this jacket 8| or to add steam to the-low-pressure zone, these expedients serve to regulate the temperature in the container 3 and are useful both in preliminarily heating the container when the apparatus is rst put into operation and in supplying additional heat to the low-pressure zone during continuous operation to assist in liberating glycerine from the soap in the bottom of the lowpressure zone 3|.

One of the features of this invention is that the soap particles are moved sidewise from the low-pressure zone, though vertical or inclined removal can in some instances be utilized. While it is usually preferable to operate the conveyor system hereinbefore described continuously, this system can be intermittently operated to intermittently removethe soap particles from the lowpressure' zone. y

An alternative system of removing the soap sidewise from the low-pressure zone, and an alternative construction of the vacuum kettle or container 3 are illustrated in Fig. 4. Here ther reaction products ilow through a pipe |20 from the heating coil and are discharged through a4 baille |23 extends inward and downward but terminates short of the shaft 36 to provide an annular space in which the vapors may move upward. The baiile |24 is of conical form and may be stationary or movable, the latter embodiment being illustrated. Movement through this tortuous path tends to separate the smaller soap particles from the vapors. In addition, the baffies provide a means for retarding the upward ilow of the vapors. l

The soap particles drop to the lower end of the container 3 and are stirred by an agitator shown as including upper and lower agitator arms |25 and |26. An agitator arm |21 preferably turns directly above the conical bottom of the container 3 and insures movement o f the soap into a throat |28 of the container.

Reciprocating means is provided for withdrawing the soap particles without breaking the vacuum in the low-pressure zone 3|. rIhis system provides a cylinder |30 in which a piston 3| is reciprocated by any suitable means such as a piston rod attached to a cross-head |30.

Av pinl |31 carried on a rotatable disc |38 fitsinto the cross-head |36 to effect reciprocation thereof. However, a suitable crank means or other reciprocating mechanism may be substituted.

As the piston |3| moves to the left in the cylinder |30 a partial vacuumis created in the right-hand end thereof so that when the piston uncovers the throat |28, the soap particles may drop into this cylinder. As the piston |3| moves to the right and covers the throat |28, the pressure in the right-hand end of the cylinder |30 progressively increases. been introduced into the cylinder |30, this soap will be compressed by this rightward movement oi' the piston |3|. When the pressure becomes suiiiciently great to overcome the action of a spring |40 normally closing a valve means |,4|, this valve means opens and allows the soap to be extruded. A's disclosed, this valve means may include a conical seat |42 adapted to receive a conical plug |43 normally seated by action of the spring |40 and by any pressure differential during the time the pressure inside the rightha-nd end of the cylinder |30 is below atmospheric. i

Similarly, when the piston |3| is moved to the right from its position shown, a partial vacuum will be created in the left-hand end of the cylinder |30 so that when the piston uncovers the throat |28, soap particles will drop into this cylinder. Subsequent leftward movement of this piston will cover the throat |28 and increase the pressure in the left-hand end of the cylinder |30 until such time as the soap is extruded from a valve I 5| similar to the valve |4| previously described. Both valves tightly seat when the pressure within the cylinder |30 decreases, thus permitting the development of sub-atmospheric pressures in the cylinder |30 so that the iiow of soap thereinto is not impeded. If desired, the degree of vacuum developed in the cylinder |30 ,may be higher than that present in the lowpressure zone 3|, in which event the soap particles will be forcibly drawn into the cylinder |30 as the throat |28 is uncovered.

If desired, the'solid soap particles alternately discharged through the valves |4| and |5| may be conducted to aconveyor system such as shown in Fig. 1 for cooling and hydration to secure a soap of desired moisture content. Use of only one of the conveyors is ordinarily. sumcient,

If sufficient soap hasv though the complete conveyor system can be means for withdrawngsad soap particles from utilized if desired.

Various changes and modifications may be made without departing from the spirit of the invention hereinbefore described with reference to two illustrative embodiments.

I claim as my invention:

1. In combination: a container; means for reducing the pressure in said container to form a low-pressure zone therein; means for continuously delivering a mixture of soap particles to said low-pressure zone to evaporate said volatile material and collect a mass of soap in said zone; an agitator in said low-pressure zone; means for moving said agitator through the soap particles in said low-pressure zone; conveyor means beneath said agitator for continuously withdrawing said soap particles from said low-pressure zone; and a star valve receiving the soap particles from said conveyor means for maintaining a sub-atmospheric pressure in said conveyor' means.

2. In combination: a container; means for reducing the pressure in said container to form a low-pressurezone therein; means for continuously delivering a mixture of soap particles to said low-pressure Zone; a first conveyor means communicating with said low-pressure zone to withdrawsaid soap particles therefrom; a pressuresealed means into which said first conveyor means discharges; asecond conveyor means receiving the soap particles from said pressure-sealed means; and means for compressing the soap particles moved by said second conveyor means to form a compressed soap mass.

3. In combination in a device for removing soap particles from a low-pressure chamber: rotatable and stationary members disposed about a common axisand providing a tapered annular passage therebetween of greater cross-sectional area at one end than at the other; means conveying the soap particles from said low-pressure zone to the larger end of said tapered annular passage; vane means on said rotatable member and disposed helically relative to said common axis and extending across said tapered annular passage for advancing said soap particles through portions of said tapered annular passage of decreasing cross-sectional area to compress said soap particles sufficiently to form a compressed mass of soap; and drive means for rotating said rotatable member about said axis.

4. A combination as defined in claim 3 including means communicating with said tapered annular passage for introducing a material into said soap moving therethrough.

5. A combination as defined in claim 3 including a means at the small cross-section end of said tapered annular passage and providing one or more orifices through which said compressed soap mass is extruded.

6. In combination: a container; an inner shell smaller than said container and positioned therein, said shell being closed at its upper end and open at its lower end to communicate with the lower section of said container and with the space between said container and said inner shell; means delivering soap particles and vapor to the interior of said inner shell whereby said vapor and soap move downward therein, said vapor rising in said space; means for retarding the upward movement of said vapors in said space; means withdrawing said vapors from said space; and

the bottom of said container.

7. Apparatus for removing glycerine from soap mixtures containing the same, which comprises, a closed glycerine vapor separating chamber, means for withdrawing and condensing vapors from said chamber to maintain a relativey high vacuum therein, meansfor heating said mixture to a temperature sufficient to cause glycerine vapors to be liberated when the mixture is delivered into said chamber, means for maintaining the heated mixture out of contact with the atmosphere and for continuously delivering the heated mixture into said chamber so that glycerine vapor is separated and withdrawn and soap is deposited in said chamber in comminuted form, and means for pushing said comminuted soap from said chamber without breaking said vacuum, said last-named means including a screw conveyor having a casing and a rotating shaft providing a tapered passage therebetween to compress said comminuted soap and form a vacuum seal.

8. Apparatus for removing glycerine from soap mixtures containing the same, which comprises, a closed vapor separating chamber, means for withdrawing vapors from said chamber to maintain a sub-atmospheric pressure therein, means for heating said mixture and for continuously delivering the heated mixtureinto said chamber so that glycerine vapor is separated and withdrawn and soap is deposited in said chamber in comminuted form, means for removing said comminuted soa-p from said chamber without impairing said sub-atmospheric pressure, said removing means having an element in the lower portion of said chamber for pushing said soap out of said chamber and means for adding water to said soap in said removing means during withdrawal while said soap is still under said sub-atmospheric pressure so as to vaporize said Water and cool said soap.

9. An apparatus for producing and cooling comminuted soap in substantially anhydrous condition comprising, in combination: a vapor separating chamber; conveyor mechanism associated therewith, said conveyor mechanism having an element positioned inY said chamber constructed and arranged to push the comminuted soap continuously from said chamber while preventing the ingress of air thereto; means for cooling the anhydrous and comminuted soap in said conveyor mechanism comprisingmeans for distributing a stream of water directly into said conveyor mechanism upon said soap and means for withdrawing water vapor from said conveyor mechanism to provide for vaporizing predetermined portions of said water whereby to cool and hydrate the comminuted soap to the desired extent.

10. In combination: apparatus, including a ,vacuum chamber, for continuously producing and depositing heated substantially anhydrous comminuted soap in said vacuum chamber; means for removing said comminuted soap from said chamber without breaking said vacuum, said means comprising a rotating element having a portion extending into. said chamber for pushing said comminuted soap out of said chamber; and

means for delivering water into direct contact with said soap to cool the same prior to discharging the soap to the atmosphere.

BENJAMIN H. THURMAN. 

